One of the main problems associated with cryptocurrencies, such as Bitcoin and Ethereum, is that of being able to adequately protect users' private keys. As we know from Chapter 2, Cryptography Essentials, the knowledge of the public key does not constitute a security issue, as it is made available to anyone interested in contacting the public key holder.
In the case of the private key, instead, it is important to guarantee its maximum confidentiality: anyone who manages to gain possession of the private key automatically becomes able to use the funds contained in the transactions referable to it, on behalf of the legitimate owner.
By knowing the private key, in fact, anyone is able to view a user's account balance, querying the transactions associated with the account and recorded within the blockchain. The commonly adopted method for managing...